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1.
Environ Sci Technol ; 58(1): 171-181, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38100468

RESUMO

A case-crossover study among 511,767 cardiovascular disease (CVD) deaths in Jiangsu province, China, during 2015-2021 was conducted to assess the association of exposure to ambient ozone (O3) and heat wave with CVD mortality and explore their possible interactions. Heat wave was defined as extreme high temperature for at least two consecutive days. Grid-level heat waves were defined by multiple combinations of apparent temperature thresholds and durations. Residential O3 and heat wave exposures were assessed using grid data sets (spatial resolution: 1 km × 1 km for O3; 0.0625° × 0.0625° for heat wave). Conditional logistic regression models were applied for exposure-response analyses and evaluation of additive interactions. Under different heat wave definitions, the odds ratios (ORs) of CVD mortality associated with medium-level and high-level O3 exposures ranged from 1.029 to 1.107 compared with low-level O3, while the ORs for heat wave exposure ranged from 1.14 to 1.65. Significant synergistic effects on CVD mortality were observed for the O3 and heat wave exposures, which were generally greater with higher levels of the O3 exposure, higher temperature thresholds, and longer durations of heat wave exposure. Up to 5.8% of the CVD deaths were attributable to O3 and heat wave. Women and older adults were more vulnerable to the exposure to O3 and heat wave exposure. Exposure to both O3 and heat wave was significantly associated with an increased odds of CVD mortality, and O3 and heat wave can interact synergistically to trigger CVD deaths.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Doenças Cardiovasculares , Ozônio , Humanos , Feminino , Idoso , Ozônio/análise , Doenças Cardiovasculares/epidemiologia , Poluentes Atmosféricos/análise , Estudos Cross-Over , Temperatura Alta , China/epidemiologia , Poluição do Ar/análise , Exposição Ambiental/análise , Material Particulado/análise
2.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612673

RESUMO

Pumpkin (Cucurbita maxima) is an important vegetable crop of the Cucurbitaceae plant family. The fruits of pumpkin are often used as directly edible food or raw material for a number of processed foods. In nature, mature pumpkin fruits differ in size, shape, and color. The Atlantic Giant (AG) cultivar has the world's largest fruits and is described as the giant pumpkin. AG is well-known for its large and bright-colored fruits with high ornamental and economic value. At present, there are insufficient studies that have focused on the formation factors of the AG cultivar. To address these knowledge gaps, we performed comparative transcriptome, proteome, and metabolome analysis of fruits from the AG cultivar and a pumpkin with relatively small fruit (Hubbard). The results indicate that up-regulation of gene-encoded expansins contributed to fruit cell expansion, and the increased presence of photoassimilates (stachyose and D-glucose) and jasmonic acid (JA) accumulation worked together in terms of the formation of large fruit in the AG cultivar. Notably, perhaps due to the rapid transport of photoassimilates, abundant stachyose that was not converted into glucose in time was detected in giant pumpkin fruits, implying that a unique mode of assimilate unloading is in existence in the AG cultivar. The potential molecular regulatory network of photoassimilate metabolism closely related to pumpkin fruit expansion was also investigated, finding that three MYB transcription factors, namely CmaCh02G015900, CmaCh01G018100, and CmaCh06G011110, may be involved in metabolic regulation. In addition, neoxanthin (a type of carotenoid) exhibited decreased accumulation that was attributed to the down-regulation of carotenoid biosynthesis genes in AG fruits, which may lead to pigmentation differences between the two pumpkin cultivars. Our current work will provide new insights into the potential formation factors of giant pumpkins for further systematic elucidation.


Assuntos
Cucurbita , Frutas , Frutas/genética , Cucurbita/genética , Multiômica , Regulação para Baixo , Carotenoides , Glucose
3.
Molecules ; 29(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38338387

RESUMO

Trilobatin (TBL) is a key sweet compound from the traditional Chinese sweet tea plant (Rubus suavissimus S. Lee). Because of its intense sweetness, superior taste profile, and minimal caloric value, it serves as an exemplary natural dihydrochalcone sweetener. It also has various health benefits, including anti-inflammatory and glucose-lowering effects. It is primarily produced through botanical extraction, which impedes its scalability and cost-effectiveness. In a novel biotechnological approach, phloretin is used as a precursor that is transformed into TBL by the glycosyltransferase enzyme ph-4'-OGT. However, this enzyme's low catalytic efficiency and by-product formation limit the large-scale synthesis of TBL. In our study, the enzyme Mdph-4'-OGT was used to screen 17 sequences across species for TBL synthesis, of which seven exhibited catalytic activity. Notably, PT577 exhibited an unparalleled 97.3% conversion yield within 3 h. We then optimized the reaction conditions of PT577, attaining a peak TBL bioproduction of 163.3 mg/L. By employing virtual screening, we identified 25 mutation sites for PT577, thereby creating mutant strains that reduced by-products by up to 50%. This research enhances the enzymatic precision for TBL biosynthesis and offers a robust foundation for its industrial-scale production, with broader implications for the engineering and in silico analysis of glycosyltransferases.


Assuntos
Flavonoides , Glicosiltransferases , Polifenóis , Glicosiltransferases/genética , Antioxidantes , Edulcorantes
4.
Biochem Biophys Res Commun ; 671: 205-214, 2023 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-37302296

RESUMO

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) provide added vascular protection beyond glucose lowering to patients with type 2 diabetes mellitus (T2DM). Endothelial progenitor cells (EPCs) are an important endogenous repair mechanism for diabetic vascular complications. Yet, whether SGLT2i protect vessels in diabetic patients by improving the function of EPCs remains to be elucidated. Here we enrolled Sixty-three T2DM patients and 60 healthy participants and 15 of T2DM group took dapagliflozin for 3 months. Retinal capillary density (RCD) was examined before and after meditation. Moreover, vasculogenic capacity of EPCs cocultured with or without dapagliflozin in vitro and in vivo (hind limb ischemia model) were assessed. Mechanically, genes related to inflammation/oxidative stress, and the AMPK signaling of EPCs were determined. Our results found T2DM demonstrated a declined RCD and a decreased number of circulating EPCs compared with healthy controls. Compared with the EPCs from healthy individuals, vasculogenic capacity of T2DM EPCs was significantly impaired, which could be restored by dapagliflozin meditation or dapagliflozin coculture. Increased expression of inflammation correlative genes and decreased anti-oxidative stress related genes expression were found in EPCs form T2DM, which were accompanied with reduced phosphorylation level of AMPK. Dapagliflozin treatment activated AMPK signaling, decreased the level of inflammation and oxidative stress, and rescued vasculogenic capacity of EPCs from T2DM. Furthermore, AMPK inhibitor pretreatment diminished the enhancement vasculogenic capacity of diabetic EPCs from dapagliflozin treatment. This study demonstrates for the first time that dapagliflozin restores vasculogenic capacity of EPCs via activating AMPK-mediated inhibition of inflammation and oxidative stress in T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Células Progenitoras Endoteliais , Humanos , Células Progenitoras Endoteliais/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Estresse Oxidativo , Glucose/metabolismo
5.
Int J Mol Sci ; 24(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37686228

RESUMO

Invertases and their inhibitors play important roles in sucrose metabolism, growth and development, signal transduction, and biotic and abiotic stress tolerance in many plant species. However, in cucumber, both the gene members and functions of invertase and its inhibitor families remain largely unclear. In this study, in comparison with the orthologues of Citrullus lanatus (watermelon), Cucumis melo (melon), and Arabidopsis thaliana (Arabidopsis), 12 invertase genes and 12 invertase inhibitor genes were identified from the genome of Cucumis sativus (cucumber). Among them, the 12 invertase genes were classified as 4 cell wall invertases, 6 cytoplasmic invertases, and 2 vacuolar invertases. Most invertase genes were conserved in cucumber, melon, and watermelon, with several duplicate genes in melon and watermelon. Transcriptome analysis distinguished these genes into various expression patterns, which included genes CsaV3_2G025540 and CsaV3_2G007220, which were significantly expressed in different tissues, organs, and development stages, and genes CsaV3_7G034730 and CsaV3_5G005910, which might be involved in biotic and abiotic stress. Six genes were further validated in cucumber based on quantitative real-time PCR (qRT-PCR), and three of them showed consistent expression patterns as revealed in the transcriptome. These results provide important information for further studies on the physiological functions of cucumber invertases (CSINVs) and their inhibitors (CSINHs).


Assuntos
Arabidopsis , Citrullus , Cucumis melo , Cucumis sativus , Humanos , Cucumis sativus/genética , beta-Frutofuranosidase , Genes Duplicados , Citrullus/genética
6.
J Nat Prod ; 84(4): 1012-1021, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33706515

RESUMO

Natural alkaloids, a large class of plant-derived substances, have attracted considerable interest because of their pharmacological activities. In this study, the in vivo pharmacokinetics and anti-inflammatory profile of anatabine, a naturally occurring alkaloid, were characterized in rodents. Anatabine was found to be bioavailable and brain-penetrant following systemic administration. Following intraperitoneal (i.p.) administration (1, 2, and 5 mg/kg), anatabine caused a dose-dependent reduction in carrageenan-induced paw edema in rats; in mice, it inhibited the production of pro-inflammatory cytokines and simultaneously elevated the levels of an anti-inflammatory cytokine in a dose-dependent manner 2 h after lipopolysaccharide challenge. Furthermore, anatabine (∼10 and ∼20 mg/kg/day for 4 weeks; inhalation exposure) had effects in a murine model of multiple sclerosis, reducing neurological deficits and bodyweight loss. Comparative studies of the pharmacokinetics and anti-inflammatory activity of anatabine demonstrated its bioequivalence in rats following i.p. administration and inhalation exposure. This study not only provides the first detailed profile of anatabine pharmacokinetics in rodents but also comprehensively characterizes the anti-inflammatory activities of anatabine in acute and chronic inflammatory models. These findings provide a basis for further characterizing and optimizing the anti-inflammatory properties of anatabine.


Assuntos
Alcaloides/farmacologia , Anti-Inflamatórios/farmacologia , Piridinas/farmacologia , Alcaloides/farmacocinética , Animais , Anti-Inflamatórios/farmacocinética , Encéfalo/metabolismo , Carragenina , Citocinas , Edema/tratamento farmacológico , Encefalomielite Autoimune Experimental/tratamento farmacológico , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Piridinas/farmacocinética , Ratos , Ratos Wistar
7.
J Transl Med ; 18(1): 26, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31948436

RESUMO

Upon publication of the original article [1], it was noticed that Jun Tao's affiliation information is not complete. The full affiliation information for Jun Tao can be found below and in the complete affiliation list of this Correction article.

8.
Arch Toxicol ; 94(6): 2179-2206, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32367274

RESUMO

The use of flavoring substances is an important element in the development of reduced-risk products for adult smokers to increase product acceptance and encourage switching from cigarettes. In a first step towards characterizing the sub-chronic inhalation toxicity of neat flavoring substances, a study was conducted using a mixture of the substances in a base solution of e-liquid, where the standard toxicological endpoints of the nebulized aerosols were supplemented with transcriptomics analysis. The flavor mixture was produced by grouping 178 flavors into 26 distinct chemical groups based on structural similarities and potential metabolic and biological effects. Flavoring substances predicted to show the highest toxicological effect from each group were selected as the flavor group representatives (FGR). Following Organization for Economic Cooperation and Development Testing Guideline 413, rats were exposed to three concentrations of the FGR mixture in an e-liquid composed of nicotine (23 µg/L), propylene glycol (1520 µg/L), and vegetable glycerin (1890 µg/L), while non-flavored and no-nicotine mixtures were included as references to identify potential additive or synergistic effects between nicotine and the flavoring substances. The results indicated that the inhalation of an e-liquid containing the mixture of FGRs caused very minimal local and systemic toxic effects. In particular, there were no remarkable clinical (in-life) observations in flavored e-liquid-exposed rats. The biological effects related to exposure to the mixture of neat FGRs were limited and mainly nicotine-mediated, including changes in hematological and blood chemistry parameters and organ weight. These results indicate no significant additive biological changes following inhalation exposure to the nebulized FGR mixture above the nicotine effects measured in this sub-chronic inhalation study. In a subsequent study, e-liquids with FGR mixtures will be aerosolized by thermal treatment and assessed for toxicity.


Assuntos
Vapor do Cigarro Eletrônico/toxicidade , Sistemas Eletrônicos de Liberação de Nicotina , Aromatizantes/toxicidade , Perfilação da Expressão Gênica , Fígado/efeitos dos fármacos , Sistema Respiratório/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Vaping/efeitos adversos , Animais , Biomarcadores/sangue , Qualidade de Produtos para o Consumidor , Feminino , Exposição por Inalação , Fígado/metabolismo , Fígado/patologia , Masculino , Ratos Sprague-Dawley , Sistema Respiratório/imunologia , Sistema Respiratório/metabolismo , Sistema Respiratório/patologia , Medição de Risco , Fatores de Tempo , Testes de Toxicidade
9.
J Transl Med ; 17(1): 368, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718666

RESUMO

BACKGROUND: Hypertension often presents with microvascular rarefaction (MVR), which is closely associated with impaired angiogenesis. Early detection of MVR is essential for systemic assessment in patient with hypertension. We aimed to determine the systemic MVR through both optical coherence tomography angiography (OCTA) and intravital capillaroscopy, and to investigate their respective efficacies and related mechanisms associated with late endothelial progenitor cells (LEPCs) dysfunction. METHODS: Seventy-one hypertensive and sixty-nine age-match normotensive subjects were included in this study. All subjects received intravital capillaroscopy for skin capillary density (SCD) and OCTA for retinal capillary density (RCD) and non-perfused areas (R-NPA). Subsequently, correlation of LEPCs activities and microvascular rarefaction were examined. RESULTS: Compared with normotensive subjects, hypertensive patients had significantly lower RCD [(52.9 ± 2.9)% vs. (57.8 ± 1.6)%, P < 0.01] and higher R-NPA [(0.12 ± 0.07) mm2 vs. (0.053 ± 0.020) mm2, P < 0.01]. SCD correlated positively with RCD but negatively with R-NPA [(RCD: OR = 0.40, 95% CI 0.25-0.67, P < 0.01); (R-NPA: OR = 0.39, 95% CI - 0.0029 to 0.0011, P < 0.01)]. The discriminative powers of RCD performed best (AUC 0.79 versus SCD AUC 0.59, P < 0.001) followed by R-NPA (AUC 0.73 versus SCD AUC 0.59, P < 0.001) for systolic blood pressure. Similar pattern is also found for diastolic blood pressure (RCD AUC 0.80 versus SCD AUC 0.54, P < 0.001; R-NPA AUC 0.77 versus SCD AUC 0.54, P < 0.001). Furthermore, LEPCs tube formation was impaired in hypertensive patients (36.8 ± 2.3 vs. 28 ± 3.7, P < 0.01). After multivariate adjustments, positive correlation existed between RCD or R-NPA with LEPCs tube formation (RCD: ß = 0.64, 95% CI 0.34-0.91, P < 0.01; R-NPA: ß = - 24.67, 95% CI - 43.14 to - 4.63, P < 0.05) but not with SCD (ß = 0.082, 95% CI 0.01-0.18, P = 0.085). CONCLUSION: Compared to intravital capillaroscopy, OCTA is a more precise technique for early detection of hypertensive microvascular rarefaction, which is associated with the fall in LEPC-mediated angiogenesis. Both of OCTA and LEPCs function can help identify hypertension-related capillary abnormality. Trail Registration The trial is a substudy of EXCAVATION-CHN1, registered at clinicaltrials.gov as NCT02817204 (June 26, 2016).


Assuntos
Células Progenitoras Endoteliais/patologia , Hipertensão/complicações , Hipertensão/fisiopatologia , Rarefação Microvascular/complicações , Rarefação Microvascular/fisiopatologia , Adulto , Pressão Sanguínea , Capilares/patologia , Capilares/fisiopatologia , Feminino , Humanos , Modelos Lineares , Masculino , Microcirculação , Análise Multivariada , Neovascularização Fisiológica , Perfusão , Curva ROC , Retina/patologia , Pele/irrigação sanguínea
10.
Nanomedicine ; 14(7): 2215-2226, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29964220

RESUMO

Inflammation and oxidative stress are two major factors that are involved in the pathogenesis of atherosclerosis. A smart drug delivery system that responds to the oxidative microenvironment of atherosclerotic plaques was constructed in the present study. Andrographolide-loaded micelle was assembled from the block copolymer of poly(ethylene glycol) and poly(propylene sulphide) (PEG-PPS) for the purpose of simultaneously decreasing inflammatory response and the level of reactive oxygen species (ROS) to treat atherosclerosis. Owing to the ROS-responsive nature of PEG-PPS, the micelle not only serves as a stimuli-responsive drug carrier to quickly release the encapsulated drug, andrographolide, but also consumes ROS by itself at the pathologic sites, upon which the expressions of pro-inflammatory cytokines are effectively suppressed and oxidative stress is alleviated. Consequently, the andrographolide-loaded micelle demonstrated remarkable therapeutic effects both in vitro and in vivo. In conclusion, the andrographolide-loaded PEG-PPS micelle can synchronically alleviate inflammation and oxidative stress, providing a promising and innovative strategy against atherosclerosis.


Assuntos
Aterosclerose/tratamento farmacológico , Diterpenos/farmacologia , Sistemas de Liberação de Medicamentos , Inflamação/tratamento farmacológico , Placa Aterosclerótica/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Animais , Aorta/patologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Diterpenos/administração & dosagem , Diterpenos/química , Portadores de Fármacos/química , Feminino , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos Knockout para ApoE , Micelas , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Polietilenoglicóis/química , Polímeros/administração & dosagem , Polímeros/química
11.
Clin Sci (Lond) ; 130(22): 2029-2042, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27729472

RESUMO

The discovery of endothelial progenitor cells (EPCs), a group of cells that play important roles in angiogenesis and the maintenance of vascular endothelial integrity, has led to considerable improvements in our understanding of the circulatory system and the regulatory mechanisms of vascular homoeostasis. Despite lingering disputes over where EPCs actually originate and how they facilitate angiogenesis, extensive research in the past decade has brought about significant advancements in this field of research, establishing EPCs as an essential element in the pathogenesis of various diseases. EPC and hypertensive disorders, especially essential hypertension (EH, also known as primary hypertension), represent one of the most appealing branches in this area of research. Chronic hypertension remains a major threat to public health, and the exact pathologic mechanisms of EH have never been fully elucidated. Is there a relationship between EPC and hypertension? If so, what is the nature of such relationship-is it mediated by blood pressure alterations, or other factors that lie in between? How can our current knowledge about EPCs be utilized to advance the prevention and clinical management of hypertension? In this review, we set out to answer these questions by summarizing the current concepts about EPC pathophysiology in the context of hypertension, while attempting to point out directions for future research on this subject.


Assuntos
Células Progenitoras Endoteliais/patologia , Hipertensão/patologia , Animais , Pressão Sanguínea , Células Progenitoras Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Humanos , Hipertensão/metabolismo , Hipertensão/fisiopatologia
12.
Int J Cardiol Cardiovasc Risk Prev ; 20: 200233, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38229680

RESUMO

Background: As an indicator of arterial stiffness, there is controversy over whether estimated pulse wave velocity (ePWV) add additional prognostic information other than cardiovascular risk factors or traditional risk estimation model in general population. Methods: Data from National Health and Nutrition Examination Survey in 1999-2018 was analyzed. Cardiovascular risk factors were collected and Framingham Risk Score (FRS) was calculated. Using all-cause and cardiovascular mortality as outcomes, Cox and restricted cubic spline (RCS) analysis was performed. Receiver operator characteristic (ROC) curves, Harrell's C-statistic and net reclassification index (NRI) analysis were used to assess whether ePWV adds additional predictive value. Results: The association between ePWV and outcomes was independent of cardiovascular risk factors (HR = 1.23 [95%CI 1.23-1.50] per m/s for all-cause mortality, and 1.52 [1.30-1.78] for cardiovascular mortality) and FRS (1.22 [1.12-1.32] for all-cause mortality, and 1.32 [1.10-1.59] for cardiovascular mortality). Except for ePWV and all-cause mortality adjusted by FRS, a liner association was found between ePWV and outcomes. For predictive value, the area under ROC and C-index of the model added with ePWV was higher than the one with FRS or risk factors alone (P < 0.01). The elevated ePWV upgraded 1338456 subjects from high-intermediate to high FRS category, and NRI was 3.61 % and 2.62 % for all-cause and cardiovascular deaths, respectively (all P < 0.001). Conclusions: In general population, the present study demonstrated the association between ePWV and all-cause, cardiovascular mortality is independent of cardiovascular risk factors and traditional risk estimated model. ePWV also added additional information to them in predicting clinical outcomes.

13.
Environ Sci Pollut Res Int ; 31(5): 7751-7774, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38170355

RESUMO

Based on the panel data of 30 provinces (municipalities and autonomous regions) in China from 2005 to 2019, this paper uses Gini coefficient decomposition and kernel density estimation to investigate the regional differences and dynamic evolution trend of rural energy carbon emission intensity in China. Then, the convergence model is used to analyze the convergence characteristics and influencing factors of carbon emission intensity. The study found the following: (1) During the observation period, the carbon emissions of coal energy and oil energy were much higher than those of gas energy. The carbon emissions of rural energy consumption experienced three stages of development, and the carbon emission intensity showed a downward trend as a whole. The spatial distribution pattern of total carbon emissions present an "adder" distribution, and the spatial agglomeration phenomenon gradually strengthens with the passage of time. (2) The Gini coefficient of China's rural energy consumption carbon emission intensity shows a trend of "Inverted N-shaped." The Gini coefficient of carbon emission intensity in the eastern and northeastern regions shows an increasing trend, while the Gini coefficient of carbon emission intensity in the western and central regions shows a downward trend. The super variable density is the main source of carbon emission intensity difference. The peak value of the main peak of the nuclear density curve of the carbon emission intensity increased significantly, the bimodal form evolved into a single peak form, and the density center moved to the left. (3) The carbon emission intensity of rural energy consumption in the whole, central, and western regions of China has the characteristic of σ convergence, while the carbon emission intensity in the eastern and northeastern regions does not have the characteristic of σ convergence. There is a significant spatial positive correlation in the carbon emission intensity, there is also a significant ß convergence characteristic, the speed of conditional ß convergence is significantly higher than that of absolute ß convergence, and the spatial interaction will further improve the convergence speed. Industrial structure, industrial agglomeration, and energy efficiency will increase the convergence speed. In terms of sub-regions, the conditional convergence rate of carbon emission intensity in the four regions shows a decreasing trend in the northeast, central, eastern, and western regions.


Assuntos
Carbono , Carvão Mineral , China , Indústrias , Análise Espacial , Desenvolvimento Econômico
14.
Environ Toxicol Chem ; 43(6): 1250-1259, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38563658

RESUMO

The microplastics (MPs) formed by broken plastic film may migrate in the soil under drip irrigation. To investigate the migration distribution of MPs in desert farmland soil under drip irrigation conditions, our study was conducted on farmland in Xinjiang (China). A MP drip irrigation penetration migration testing device was set up in combination with Xinjiang farmland irrigation methods to conduct a migration simulation experiment. The results showed that the migration amount of MPs in soil was significantly positively correlated with the amount of drip irrigation, and significantly negatively correlated with the soil depth; in addition, the relationship between the migration amount of MPs in different types of soil was: clay < sandy loam < sandy soil. Under drip irrigation conditions, the migration rates of MPs were 30.51%, 19.41%, and 10.29% in sandy soil, sandy loam soil, and clay, respectively. The migration ability of these three particle sizes of polyethylene MPs in soil was ranked as follows: 25 to 147 µm > 0 to 25 µm > 147 to 250 µm. When the drip irrigation volume was 2.6 to 3.2 L, horizontal migration distances of MPs exceeded 5 cm, and vertical migration distances reached more than 30 cm. Our findings provide reference data for the study of soil MP migration. Environ Toxicol Chem 2024;43:1250-1259. © 2024 SETAC.


Assuntos
Irrigação Agrícola , Clima Desértico , Microplásticos , Poluentes do Solo , Solo , Microplásticos/análise , Poluentes do Solo/análise , Solo/química , China , Monitoramento Ambiental , Fazendas
15.
Biotechnol Biofuels Bioprod ; 17(1): 60, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711141

RESUMO

BACKGROUND: The structural diversity of extracellular polymeric substances produced by microorganisms is attracting particular attention. Poly-gamma-glutamic acid (γ-PGA) is a widely studied extracellular polymeric substance from Bacillus species. The function of γ-PGA varies with its molecular weight (Mw). RESULTS: Herein, different endogenous promoters in Bacillus licheniformis were selected to regulate the expression levels of pgdS, resulting in the formation of γ-PGA with Mw values ranging from 1.61 × 103 to 2.03 × 104 kDa. The yields of γ-PGA and exopolysaccharides (EPS) both increased in the pgdS engineered strain with the lowest Mw and viscosity, in which the EPS content was almost tenfold higher than that of the wild-type strain. Subsequently, the compositions of EPS from the pgdS engineered strain also changed. Metabolomics and RT-qPCR further revealed that improving the transportation efficiency of EPS and the regulation of carbon flow of monosaccharide synthesis could affect the EPS yield. CONCLUSIONS: Here, we present a novel insight that increased pgdS expression led to the degradation of γ-PGA Mw and changes in EPS composition, thereby stimulating EPS and γ-PGA production. The results indicated a close relationship between γ-PGA and EPS in B. licheniformis and provided an effective strategy for the controlled synthesis of extracellular polymeric substances.

16.
ACS Omega ; 9(16): 18314-18326, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38680381

RESUMO

Coal seams of the Yangxia Formation are widespread in the northern part of the Kuqa Depression in the Tarim Basin. During the thermal evolution of the coal seams, the generated fluids of different periods and natures have a significant impact on tight sandstone reservoirs. To further investigate the diagenetic characteristics and reservoir genesis of the tight sandstones due to the influence of coal seams, an in-depth exploration of the causes of dissolution and cementation in the reservoirs was conducted through thin-section casting, cathode luminescence, scanning electron microscopy, carbon-oxygen isotopic analyses, and X-ray diffraction of whole rock and authigenic clay minerals, along with burial evolution history and fluid evolution history. It is suggested that two phases of acidic fluids are mainly produced during the thermal evolution process of coal seams, including an early humic acid and a late organic carboxylic acid. The early phase humic acid plays a purifying role in reservoirs with coarse particles, rigidity-rich particles, and good permeability conditions. It selectively dissolves sedimentary calcareous mud and calcite, and the dissolution products are completely migrated. At the same time, it inhibits early carbonate cementation. The late organic carboxylic acid will dissolve potassium feldspar and some volcanic rock debris, and the dissolution products are difficult to migrate under the sealing conditions caused by lithological differences, which often take the cementation form of siliceous overgrowth and kaolinite or illite. In addition to the cementation resulting from the dissolution products of acidic fluids produced by the coal seams, the CO2-rich fluids generated by the coal seam thermal evolution will combine with ions such as Ca2+ from different sources, resulting in two phases of carbonate cementation. Based on the above research, this study summarizes a set of diagenetic evolution models for coal-bearing reservoirs.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38237126

RESUMO

Introduction: Olivetolic acid (OLA) is a key intermediate in cannabidiol (CBD) synthesis, and cannabinoids are important neuroactive drugs. However, the catalytic activity of olivetolic acid synthase (OLS), the key enzyme involved in OLA biosynthesis, remains low and its catalytic mechanism is unclear. Materials and Methods: In this study, we conducted a scrupulous screening of the pivotal rate-limiting enzyme and analyzed its amino acid sites that are critical to enzyme activity as validated by experiments. Results: Through stringent enzyme screening, we pinpointed a highly active OLS sequence, OLS4. Then, we narrowed down three critical amino acid sites (I258, D198, E196) that significantly influence the OLS activity. Conclusions: Our findings laid the groundwork for the efficient biosynthesis of OLA, and thereby facilitate the biosynthesis of CBD.

18.
Eur J Pharm Sci ; 194: 106693, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38184016

RESUMO

Inhalation enables the delivery of drugs directly to the lung, increasing the retention for prolonged exposure and maximizing the therapeutic index. However, the differential regional lung exposure kinetics and systemic pharmacokinetics are not fully known, and their estimation is critical for pulmonary drug delivery. The study evaluates the pharmacokinetics of hydroxychloroquine in different regions of the respiratory tract for multiple routes of administration. We also evaluated the influence of different inhaled formulations on systemic and lung pharmacokinetics by identifying suitable nebulizers followed by early characterization of emitted aerosol physicochemical properties. The salt- and freebase-based formulations required different nebulizers and generated aerosol with different physicochemical properties. An administration of hydroxychloroquine by different routes resulted in varied systemic and lung pharmacokinetics, with oral administration resulting in low tissue concentrations in all regions of the respiratory tract. A nose-only inhalation exposure resulted in higher and sustained lung concentrations of hydroxychloroquine with a lung parenchyma-to-blood ratio of 386 after 1440 min post-exposure. The concentrations of hydroxychloroquine in different regions of the respiratory tract (i.e., nasal epithelium, larynx, trachea, bronchi, and lung parenchyma) varied over time, indicating different retention kinetics. The spatiotemporal distribution of hydroxychloroquine in the lung is different due to the heterogeneity of cell types, varying blood perfusion rate, clearance mechanisms, and deposition of inhaled aerosol along the respiratory tract. In addition to highlighting the varied lung physiology, these results demonstrate the ability of the lung to retain increased levels of inhaled lysosomotropic drugs. Such findings are critical for the development of future inhalation-based therapeutics, aiming to optimize target site exposure, enable precision medicine, and ultimately enhance clinical outcomes.


Assuntos
Hidroxicloroquina , Nebulizadores e Vaporizadores , Ratos , Animais , Hidroxicloroquina/metabolismo , Distribuição Tecidual , Aerossóis , Administração por Inalação , Pulmão/metabolismo , Sistemas de Liberação de Medicamentos
19.
Water Res ; 230: 119527, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36580800

RESUMO

Production of medium-chain carboxylic acids (MCCAs) by chain elongation (CE) presents a competitive alternative to conventional products of methane in anaerobic digestion treating organic waste streams, considering energy recovery, economic, and environmental profits. However, the system stability and performance largely rely on the selective suppression of methanogens while stimulation of CE bacteria. Commercial inhibitors such as 2-bromoethanesulfonic sodium (BES) was shown to be effective, but controversial conclusions exist on its inhibition characteristics and the inhibition mechanism remains unclear. Therefore, this study systematically investigated the responses of methanogenesis in granular sludge to various BES levels, focusing on methane production, methanogenic pathway, dynamic populations, electron transport and energy metabolism. Results showed that compared with the control, 3.0 g/L BES was sufficient to induce a 72.9% reduced level on accumulative methane production by the end of 4 cycles (28 days), which was likely to be attributed to the significantly suppressed metabolic pathways and intracellular regulations. Specifically, BES suppressed the electron transport via unproper electron carriers and reduced electron amount as indicated by the decreased level of enzymes and genes involved such as coenzyme F420, CO dehydrogenase and NADH:ubiquinone reductase (H+-translocating). Moreover, BES regulated the intracellular energy metabolism, leading to the impeded ATP synthesis but enhanced ATP consumption as evidenced by the variations on the activity or abundance of acetate kinase, A1Ao-ATP synthase, nitrogenase and ATP citrate synthase. Additionally, BES enriched hydrogenotrophic methanogenesis over acetoclastic one as supported by variations on the archaeal community structures and regulations of differentially expressed genes involved. Moreover, BES also reduced the contents of both protein and carbohydrate in extracellular polymeric substances (EPS). This study is expected to enhance understanding of BES contribution to methanogenesis inhibition but MCCAs production in CE bioreactors.


Assuntos
Ácidos Alcanossulfônicos , Bactérias , Bactérias/metabolismo , Anaerobiose , Esgotos/química , Trifosfato de Adenosina/metabolismo , Metano/metabolismo , Reatores Biológicos/microbiologia
20.
Front Pharmacol ; 14: 928821, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37089950

RESUMO

Cholesterol and its metabolites have important biological functions. Cholesterol is able to maintain the physical properties of cell membrane, play an important role in cellular signaling, and cellular cholesterol levels reflect the dynamic balance between biosynthesis, uptake, efflux and esterification. Cholesterol metabolism participates in bile acid production and steroid hormone biosynthesis. Increasing evidence suggests a strict link between cholesterol homeostasis and tumors. Cholesterol metabolism in tumor cells is reprogrammed to differ significantly from normal cells, and disturbances of cholesterol balance also induce tumorigenesis and progression. Preclinical and clinical studies have shown that controlling cholesterol metabolism suppresses tumor growth, suggesting that targeting cholesterol metabolism may provide new possibilities for tumor therapy. In this review, we summarized the metabolic pathways of cholesterol in normal and tumor cells and reviewed the pre-clinical and clinical progression of novel tumor therapeutic strategy with the drugs targeting different stages of cholesterol metabolism from bench to bedside.

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